1. Field
The present disclosure relates generally to an improved data processing system and in particular to a method and apparatus for monitoring components. Still more particularly, the present disclosure relates to a method, apparatus, and computer usable program code for monitoring components for a vehicle.
2. Background
Safety and reliability of a system, such as an aircraft, is important when operating a system with a minimal risk of loss. With respect to vehicles, a safe vehicle is a vehicle that can be operated in a manner that mitigates the potential for a loss of human life and/or the vehicle. To avoid these types of situations, a health monitor system is employed to monitor the operation of the vehicle and determine when the vehicle is operating as designed and in a manner that minimizes a potential loss. An example of a health monitor system is an electronic unit that tracks a physical parameter, such as the behavior of a single subsystem or a line replaceable unit within the vehicle. In some cases, sensors may be distributed throughout the vehicle as a network to obtain information about the state of the vehicle.
An aircraft may contain a health monitor system that monitors various subsystems in the aircraft. Current health monitor systems focus on monitoring components in the aircraft to identify component failures or indications that component failures may occur. The monitoring is performed by gathering data from these components or sensors associated with the components. For example, a health monitor system may be implemented for monitoring hydraulic pumps, switches, and motors used in aircraft subsystems. These types of subsystems are typically used to actuate components or systems, such as flight control surfaces, reverse mechanisms, landing gear, and cargo doors.
As an example, an aileron control is a subsystem in an aircraft that controls the position of ailerons. Ailerons are hinged control surfaces attached to the trailing edge of an aircraft wing, and are used to control the bank angle of the aircraft by changing lift on a wing. Determining whether a control system for an aileron has failed or may fail is important for safe operation of the aircraft. Aileron control surface oscillations at certain frequencies and sufficient amplitudes could result in excessive fatigue damage or failure of airplane structure due to body or wing resonance. An oscillation may occur if a component of the control system for the aileron fails or is operating improperly.
One example of this type of failure is that an incorrect positioning command may be sent to the control for the aileron, causing the oscillations. In another example, the mechanical breaking of a feedback wire component within an electro-hydraulic servo actuator could result in an unstable system and uncommanded control surface oscillations. In many applications, if a failure is detected in one control system component, that component may be deactivated and a redundant component may be activated to perform the same function.
Currently, in monitoring electrical and/or digital flight control systems for failures, position sensors are often placed on the electro-hydraulic servo valve spool within a hydraulic servo actuator. This type of monitoring requires an additional sensor and associated wiring from the sensor to the electronics processing the data, because this sensor is not required for operation of the control system. The use of additional sensors and wiring for the sensors increases the cost and weight of an aircraft and reduces the aircraft's reliability.